High rotation linkage assembly

ABSTRACT

The addition of a thumb to a bucket of a work machine allows more uses for the work machine than having only the bucket. These uses, however, are often limited to the capabilities of the linkage of the thumb and its ability to rotate the thumb with the bucket. An attachment arrangement for a load-bearing member of a work machine for attaching the implement to the load-bearing member, comprises an implement, an actuator, and a high rotation linkage assembly rotatably attaching the implement to the load-bearing member and to the actuator, the high rotation linkage assembly structured and arranged to allow the implement to have a range of rotation of at least 190 degrees.

TECHNICAL FIELD

[0001] This invention relates generally to a high rotation linkageassembly, and, more particularly, to a high rotation linkage assemblyrotatably attached to a thumb that allows full rotation of the thumb.

BACKGROUND

[0002] Work machines such as backhoe loaders, excavators, or othersimilar work machines use counteracting thumbs and buckets to grasp,hold, and lift odd-shaped articles such as pipes, structural components,and the like, similar to the thumb of a human hand. When used to performthis grasping, holding, or lifting function, a counteracting thumb isnormally rotatably attached to a stick, lift arm assembly, or a bucketof the work machine to accomplish the grasping, holding, and liftingfunction. The high rotation linkage assembly used to rotate the thumbdictates the thumb's ability to retract fully to allow normal operationof the bucket and the thumb's ability to fully rotate so as to followthe bucket path throughout the range of rotation of the bucket.

[0003] One known linkage design is disclosed in U.S. Pat. No. 4,283,866issued to Ogawa on Aug. 18, 1981. It discloses a convertible bucketattachment having a pair of brackets, each to which the joining portionsof the bucket proper, the sub-bucket, and the lower pivot of thesub-link member are rotatably attached. The high rotation linkageassembly of this design will not allow the sub-bucket to follow the fullrotation of the bucket proper from the dump cycle to the curl cyclewhile applying clamping force on the bucket proper throughout thisrotation. More specifically, the high rotation linkage assembly of thisdesign will not allow the sub-bucket to rotate more than 190 degrees.

[0004] The present invention is directed to overcoming one or more ofthe problems as set forth above.

SUMMARY OF THE INVENTION

[0005] In one aspect of the present invention, an attachment arrangementfor a load-bearing member of a work machine comprises an implementrotatably attached to the load-bearing member, an actuator attached tothe load-bearing member, and a high rotation linkage assembly rotatablyattaching the implement to the load-bearing member and to the actuator,the high rotation linkage assembly structured and arranged to allow theimplement to have a range of rotation of at least 190 degrees.

[0006] In another aspect of the present invention, an attachmentarrangement for a load-bearing member of a work machine comprises afirst implement rotatably attached to the load-bearing member, a secondimplement rotatably attached to the load-bearing member, an actuatorattached to the load-bearing member, and a high rotation linkageassembly rotatably attaching one of the first implement and the secondimplement to the load-bearing member, the high rotation linkage assemblystructured and arranged to allow the first implement and the secondimplement to have substantially the same range of rotation.

[0007] In the present invention, an attachment arrangement for aload-bearing member of a work machine comprises an implement rotatablyattached to the load-bearing member, an actuator attached to theload-bearing member, and a high rotation linkage assembly rotatablyattaching the implement to the load-bearing member and to the actuator,the high rotation linkage assembly structured and arranged to allow theimplement to have a range of rotation of at least 190 degrees. Rotationof greater than 190 degrees of the implement produces a more usefulimplement that can function in positions it may not otherwise had beenable to function.

BRIEF DESCRIPTION OF THE DRAWINGS

[0008] For a better understanding of the present invention, referencemay be made to the accompanying drawings in which:

[0009]FIG. 1 is a diagrammatic side view of a high rotation linkageassembly for a thumb rotatably attached with a bucket of a work machine,the bucket being in the open position and the thumb being disengagedfrom the bucket;

[0010]FIG. 2 is a diagrammatic side view, in perspective, of a firstlink; and

[0011]FIG. 3 is a diagrammatic side view, in perspective, of a secondlink.

DETAILED DESCRIPTION

[0012] Referring to the drawings, FIG. 1 shows a load-bearing member100, for example a boom, stick, lift arm or the like, of a work machine(not shown) having an end portion 105 and having a lower surface 115. Apair of implements comprising, for exemplary purposes herein, a firstimplement being a bucket 120 and a second implement being a thumb 125,is rotatably attached in proximity to the end portion 105 of theload-bearing member 100 by means of a pin 130. In addition, at least oneof the implements 120 or 125 is shown attached to the load-bearingmember 100 by an attachment arrangement 134 of the present invention.The attachment arrangement 134 includes a high rotation linkage assembly135 that is rotatably attached to the thumb 125 by means of a pin 140 ata first rotatable attachment point 142, and is rotatably attached to theload-bearing member 100 by means of a pin 145 at a second rotatableattachment point 150. The attachment arrangement 134 further includes anactuator, such as a hydraulic cylinder 155, attached to the lowersurface 115 of the load-bearing member 100, having a rod end 160 that isrotatably attached to the high rotation linkage assembly 135 by means ofa pin 165 at a third rotatable attachment point 167. The hydrauliccylinder 155 is adapted to be extended and retracted to rotate andthereby curl and uncurl the thumb 125.

[0013] The high rotation linkage assembly 135 includes a pair of firstlinks (one shown), each designated herein as 170, and a second link 175.Each first link 170 has a first-end portion 180, a second-end portion185, and an extension portion 190 extending from the first-end portion180. The first-end portion 180 is rotatably attached to the rod end 160of the hydraulic cylinder 155 at the third rotatable attachment point167, and the second-end portion 185 is rotatably attached to theload-bearing member 100 at the second rotatable attachment point 150.The second link 175 has a first-end portion 192 and a second-end portion195. The first-end portion 192 is rotatably attached to the extensionportion 190 of the first link 170 by a pin 196 at a fourth rotatableattachment point 198, and the second-end portion 195 is rotatablyattached to the thumb 125 at the first rotatable attachment point 164.As shown in FIG. 1, the second rotatable attachment point 150, the thirdrotatable attachment point 167, and the fourth rotatable attachmentpoint 198 define non-co-linear rotatable attachment points irrespectiveof the location of the high rotation linkage assembly 135 in itsrotation.

[0014] With reference to FIG. 2, further details of the first link 170will now be described. It should be understood that each first link 170is substantially identical, and, as such, only one will be described.The first link 170 includes a long member 210 having a long member longaxis 211, an aperture 225 provided in the first-end portion 180, andanother aperture 230 provided in the second-end portion 185. Theextension portion 190 has an extension portion long axis 233, afirst-end portion 240, and a second-end portion 245. Each suchrespective end portion 240 and 245 has an aperture 250 and 255 providedtherein, respectively.

[0015] The first-end portion 180 of the long member 210 is attached tothe first-end portion 240 of the extension portion 190 by a hollowconnection member, such as a tubular member 260, sized to receive thepin 165. The tubular member 260 is rigidly attached, by welding or othersuitable process, to both the long member 210 and the extension portion190 such that the tubular member 260 is in concentric alignment withapertures 225 and 250. As shown, the long member 210 and extensionportion 190 of the first link 170 are attached such that the long memberlong axis 211 is oriented in a non-parallel relationship with theextension portion long axis 233. Such a showing, however, is forexemplary purposes only and it is contemplated that other geometries maybe used without deviating from the spirit of the present invention.

[0016] In FIG. 3, the second link 175 includes a pair of elements 300and 305 of substantially equal length and a pair of hollow connectionmembers, such as tubular members 310 and 315, of substantially equallength. Each element 300 and 305 has first-end portions 320 and 325,respectively, and second-end portions 330 and 335, respectively. Eachend portion 320, 325, 330, and 335 having respective apertures 340, 345,350, and 355 provided therein. The tubular member 310 is insertedthrough the apertures 340 and 345 to attach the elements 300 and 305together at the first-end portions 320 and 325 thereof to form thefirst-end portion 192 of the second link 175. Once the tubular member310 is inserted into the apertures 340 and 345, the tubular member 310is rigidly attached, by welding or other suitable process, to theelements 300 and 305 at the apertures 340 and 345, respectively, suchthat the tubular member 310 is in concentric alignment with apertures340 and 345. Further, the tubular member 315 is inserted throughapertures 350 and 355 to attach the elements 300 and 305 together at thesecond-end portions 330 and 335 thereof to form the second-end portion195 of the second link 175. Once the tubular member 315 is inserted intoapertures 350 and 355, the tubular member 315 is rigidly attached, bywelding or other suitable process, to elements 300 and 305 at theapertures 350 and 355, respectively such that the tubular member 315 isin concentric alignment with apertures 350 and 355.

[0017] Finally, the second link 175 has a geometry that is substantiallynon-linear. As shown in FIG. 3, the second link 175 has a generallyconvex shape that bends away from the load-bearing member 100 when thesecond link 175 is attached to the load-bearing member 100 in theintended manner. Such a showing, however, is for exemplary purposes onlyand it is contemplated that other geometries, such as a straight line,may be used without deviating from the spirit of the present invention.The appropriate geometry depends upon the location of the secondrotatable attachment point 150, the length of the load-bearing member100, the length of the hydraulic cylinder 155, the type of thumb 125that is used, the particular work machine on which the thumb 125 isattached, or other factors. As used herein, convex is to be understoodto not be limited to a curved shape, but is intended to encompasscurved, angular, or other like shapes.

INDUSTRIAL APPLICABILITY

[0018] Thumbs are often attached to buckets to create a gripper,grapple, or the like to grasp, hold, and lift odd-shaped items such aslogs, pipes, and structural components. During this sort of operation,the thumb's rotation must follow that of the bucket's to maintain agripping force on the item between the thumb and the bucket throughoutrotation thereof. The high rotation linkage assembly 135 of the presentinvention is structured and arranged to allow the thumb 125 to havesubstantially the same range of rotation as the bucket 120 so that thethumb 125 can stay in contact with the bucket 120 throughout thebucket's 120 range of rotation, or, at least, to allow the thumb 125 torotate more than 190 degrees relative to the load-bearing member 100.

[0019] More particularly and with reference to FIG. 1, one or more ofthe following factors allows the second link 175 to be unencumbered bythe load-bearing member 100 as the high rotation linkage 135 rotates thethumb 125: (i) the distance D₁ between the second rotatable attachmentpoint 150 and the third rotatable attachment point 167 relative to thedistance D₂ between the second rotatable attachment point 150 and theend portion 105 of the load-bearing member 100, (ii) the distance D₃between the first rotatable attachment point 142 and the fourthrotatable attachment point 198 relative to the distance D₂ between thesecond rotatable attachment point 150 and the end portion 105 of theload-bearing member 100, and (iii) the non-linear geometry of the secondlink 175.

[0020] The aforementioned factors and how they allow the thumb 125 tohave the range of rotation will now be discussed. The distance D₁ beinggreater than D₂ allows the second link 175 to extend beyond the endportion 105 of the load-bearing member 100 as the thumb 125 rotates pastthe load-bearing member 100 such that it is unencumbered by theload-bearing member 100 during such rotation. In addition, oralternatively, the distance D₃ being greater than D₂ allows the secondlink 175 to extend beyond the end portion 105 of the load-bearing member100 as the thumb 125 rotates past the load-bearing member such that itis unencumbered by the load-bearing member 100 during such rotation.Furthermore, the non-linear geometry of the second link 175 allows thesecond link 175 to be unencumbered by the load-bearing member 100 whilealso allowing the thumb 125 to remain in contact with the bucket 120 asthe thumb 125 rotates past the end portion 105 of the load-bearingmember 100.

[0021] Other aspects, objects and advantages of the invention can beobtained from a study of the drawings, the disclosure and the appendedclaims.

1. An attachment arrangement for a load-bearing member of a workmachine, comprising: an implement rotatably attached to the load-bearingmember; an actuator attached to the load-bearing member; and a highrotation linkage assembly rotatably attaching the implement to theload-bearing member and to the actuator, the high rotation linkageassembly structured and arranged to allow the implement to have a rangeof rotation of at least 190 degrees.
 2. The attachment arrangement ofclaim 1 wherein the implement is a thumb.
 3. The attachment arrangementof claim 1 wherein the high rotation linkage assembly comprises: a firstlink having first and second-end portions and an extension portionextending from the first-end portion, the first-end portion of the firstlink being rotatably attached to the load-bearing member at a secondrotatable attachment point, and the second-end portion of the first linkbeing rotatably attached to the actuator at a third rotatable attachmentpoint; and a second link having first and second-end portions, thefirst-end portion of the second link being rotatably attached to theimplement at a first rotatable attachment point, the second-end portionof the second link being rotatably attached to the extension portion ofthe first link at a fourth rotatable attachment point.
 4. The attachmentarrangement of claim 3 wherein the extension portion further has anextension portion long axis and the first link further comprises a longmember having a long member long axis oriented in a non-parallelrelationship with the extension portion long axis.
 5. The attachmentarrangement of claim 3 wherein a distance between the first rotatableattachment point and the fourth rotatable attachment point is greaterthan a distance between the second rotatable attachment point and theend portion of the load-bearing member.
 6. The attachment arrangement ofclaim 3 wherein a distance between the second rotatable attachment pointand the third rotatable attachment point is greater than a distancebetween the second rotatable attachment point and the end portion of theload-bearing member.
 7. The attachment arrangement of claim 3 whereinthe second link has a convex shape bent away from the load-bearingmember when attached with the load-bearing member.
 8. An attachmentarrangement for a load-bearing member of a work machine, comprising: afirst implement rotatably attached to the load-bearing member; a secondimplement rotatably attached to the load-bearing member; an actuatorattached to the load-bearing member; and a linkage assembly rotatablyattaching the second implement to the load-bearing member, the linkageassembly structured and arranged to allow the first implement and thesecond implement to have substantially the same range of rotation. 9.The attachment arrangement of claim 8 wherein the first implement is abucket and the second implement is a thumb.
 10. The attachmentarrangement of claim 8 wherein the rotation linkage assembly comprises:a first link having first- and second-end portions and an extensionportion extending from the first-end portion, the first-end portion ofthe first link being rotatably attached to the actuator at a thirdrotatable attachment point, the second-end portion of the first linkbeing rotatably attached to the load-bearing member at a secondrotatable attachment point; and a second link having first andsecond-end portions, the first-end portion of the second link beingrotatably attached to the extension portion of the first link at afourth rotatable attachment point and the second-end portion of thesecond link being rotatably attached to the second implement at a firstrotatable attachment point.
 11. The attachment arrangement of claim 10wherein the extension portion further has an extension portion long axisand the first link further comprises a long member having a long memberlong axis oriented in a non-parallel relationship with the extensionportion long axis.
 12. The attachment arrangement of claim 10 wherein adistance between the second rotatable attachment point and the thirdrotatable attachment point is greater than a distance between the secondrotatable attachment point and the end portion of the load-bearingmember.
 13. The attachment arrangement of claim 10 wherein a distancebetween the first rotatable attachment point and the fourth rotatableattachment point is greater than a distance between the second rotatableattachment point and the end portion of the load-bearing member.
 14. Theattachment arrangement of claim 10 wherein the second link has a convexshape bent away from the load-bearing member when attached with theload-bearing member.
 15. The attachment arrangement of claim 10 whereinthe second implement has a range of rotation of at least 190 degrees.16. An attachment arrangement for an implement of a work machine, theattachment arrangement comprising: a load-bearing member having an endportion; an implement attached to the load-bearing member in proximityto the end portion; a first link having first and second-end portionsand an extension portion extending from the first-end portion, thefirst-end portion of the first link being rotatably attached to anactuator at a third rotatable attachment point, the second-end portionof the first link being rotatably attached to the load-bearing member ata second rotatable attachment point a predetermined distance from theend portion of the load-bearing member; and a second link having firstand second-end portions, the second-end portion being rotatably attachedto the implement at a first rotatable attachment point, the second-endportion being rotatably attached to the extension portion of the firstlink at a fourth rotatable attachment point, the second, third, andfourth rotatable attachment points defining non-co-linear attachmentpoints.
 17. The attachment arrangement of claim 16 wherein the implementis a thumb.
 18. The attachment arrangement of claim 16 wherein thepredetermined distance is less than a distance between the second andthird rotatable attachment points.
 19. The attachment arrangement ofclaim 16 wherein the first link and the second link are structured andarranged to allow the implement to have a range of rotation of at least190 degrees.
 20. The attachment arrangement of claim 16 wherein theextension portion further has an extension portion long axis and thefirst link further comprises a long member having a long member longaxis oriented in a non-parallel relationship with the extension portionlong axis.
 21. An attachment arrangement for a load-bearing member of awork machine comprising: a load-bearing member; a first implementrotatably attached to the load-bearing member; a first actuator attachedto the load-bearing member applying a force to the first implement tomove the first implement relative to the load-bearing member; a secondimplement rotatably attached to the load-bearing member; a secondactuator attached to the load-bearing member applying a force to thesecond implement to move the second implement relative to theload-bearing member, the second actuator moving the second implementindependently of the first implement; and a linkage assembly rotatablyattaching the second implement to the load-bearing member, the linkageassembly allowing each of the first implement and the second implementto have a range of rotation of at least approximately 190 degrees. 22.An attachment arrangement according to claim 21 wherein: the firstimplement is an earth-excavating bucket; and the second implement is athumb which can move under force of the second actuator in an oppositedirection of the bucket to apply a pinching force to an object betweenthe bucket and the thumb.
 23. An attachment arrangement for aload-bearing member of a work machine comprising: a load-bearing member;a bucket rotatably attached to the load-bearing member; a first actuatoroperatively attached to and applying a force to the bucket to rotate thebucket relative to the load-bearing member; a thumb rotatably attachedto the load-bearing member and adapted to produce a pinching between thebucket and the thumb; a second actuator applying a force to the thumb torotate the thumb relative to the load-bearing member; a linkage assemblyconnecting the second actuator to the thumb, the linkage assemblycomprising: a first link; and a second link; wherein the first link isattached at a first end thereof to the load-bearing member and the firstlink is attached at a second end thereof opposite its first end to afirst end of the second link, the second link is attached at a secondend thereof opposite its first end to the thumb; and wherein the secondactuator is attached to the first link at a point in between the firstend and second end of the first link.
 24. An attachment arrangementaccording to claim 23 wherein the thumb has a range of motion of atleast approximately 190 degrees relative to the load-bearing member.